Air compressor



May 22, 1923. 1,456,089

' D. C. BAKER AIR COMPRESSOR Filed April 7. 1921 2 Sheets-Sheet? EPT- mmm T Mohn ya Patented-May 22.-, v19gl' i rs N Frio 'DEXTERC BAKER, on OAKLAND, CALIroRNIA, AssIGNoR To BAKER-HANSEN MANU- FACTURING COMPANY, or OAKLAND, CALIFORNIA.

AIR COMPRESSOR. v 'i Application filed April 7, 1921. Serial No. 459,220.

To all 'whom it may concern:

Be it known that I, DEXTER C'. BAKER, a citizen of the United States, and resident of Oakland,l county of Alameda, and State of California, have invented a new and useful Air Compressor, of whichfthe following is a specication. Q

This invention relates to air compressors', and has for `its object to provide an improved construction in devices of this character whereby air may be pumped into a storage container in an ,economical and eiiicient manner.

ln thel accompanying drawing which illustrates. the preferred embodiment of the ,invention Figure 1 is a horizontal section through thi-compressor on the line 1-1,

.Figure 4; Figure 2 is a detail end view of the eccentric head of drive shaft; Figure 3 is afdetail sectional view of .the valve mounting; Figure 4 is a cross-section through the compressor; Figure 5 is a longitudinal section on the line 5 5 Figure 4; Figure 6 is a plan view of the pistons and eccentric drive connection; Figure 7 is a to-p plan view partly in section of the dome shaped breather communication into the crank case and Figure 8 is a horizontal section on the line 8-8 Figure 4.

Referring to the drawing in detail (1) and (2) represent cylinders of different stages which are preferably cast en-bloc and include 'fins fo-r coo-ling purposes. The

cylinders are cast in'co-axial alignment and connected by a crank case (4) having a lubricant well (5). f

The ends ofeach one of the cylinders are closed by heads (2a) and (3a) with the perforated cover lpieces (6) and (7 interposed betwcenthe heads and the cylinders. Suitable bol-ts (7a) may be employed for securing the heads and cover plates upon the cylinder ends.

Positionedfor reciprocation with the cylinders are the pistons (8) and (9) the dimensions of which corresponding to the dimensions of the cylinders. These pistons are rigidly connected one with the other by an intermediate webb (10) which is arranged to one-side of the axis of the/pistons to provide a space between the pistons for the eccentric drive which preferably consists in a shaft (11) driven by a suitable power medium and with' its opposite end introduced into thecrank case between the .cyl-

inders through a. stepped sleeve (12) made to engage a similar stepped opening (13) in the crank case casting. The sleeve (12) being secured to the outer ange of the opening by bolts (14), arranged at each end of the sleeve (12) is4 an antifriction bear- Ving (15).

The drive end of the shaft (11) is made with an eccentric head'consisting of a disk (16) which is positioned on the shaft oft' fcenter and with'I a stud (17) on the opposite face ofthe-.disk positioned also 0E center and diametrically op-posite the shaft.

Mounted on the web (10)v andpre'ferably within the walls of the piston (9) by means of a studded anchor pin (18) is a duplex crank yoke (19). This yoke is mounted free to rock about its pivoted mounting with its opposite free end made to receive thestud (17) of the eccentric head of the shaft (11). The stud is presented in an antifriction bearing (20) which in turn is confined in the free end o-f the yoke and a second antifriction bearing is provided for the pivoted connectionof the yoke with the studded end ofthe anchor pin (18).

Again referring to the anchor pin (18) it is to be noted that the same extends through a radial opening in the enlarged casting (10a) of the webb (10) between the walls of the cylinder (9). The pin is anchored by the guide rod (21) for the cylinders which has a threaded engagement with a With reference to the introduction of the' air into the compressor attention is first called to the cylinder head (3a) in which (3b) is the primary intake the same establishing a. communication between the atmosphere and the annular distributing mani'- vmi fold channel (3). This channel communicates with the outer annular row of perforations (39)) in the plate (7) and through these perforations into the compression chamber ofthe cylinder (1). `All of 'the perforations in each row in both plates (7) are connected one with the other by annular grooves cut in both sides of the plates (see Figure l). Positioned on the inside of the plate (7) for the cylinder (l) are a pair` of superimposed disks (3e) the inner disc having a diameter to overlap the openings (3d) but the edge of the disc is adapted to ieX upon a suction stroke of the piston (9) to admit air into the cylinder (l) from the manifold channel (3C). The smaller or outer one of the discs acts so as to rigidly hold the inner or larger disc flat against the inner face of its plate (7 while permitting` the edge of the disc to fleX as above stated. The inner annular row of openings (3f) are controlled by the superimposed dises (3g) each of which having the same diameter and mounted on the opposite face of the plate (7) from the discs (3e). The discs (3) are constructed with openings (3h) which are in constant registry with the openings (3f) in the plate so that upon a compression stroke of the piston (9) the air in the cylinder may be forced into the central chamber (3i) by overcoming the influence of the spring which maintains the discs (3g) over the openings (3f) thus moving the discs away from the openings and establishing a communication between the cylinder and the chamber. As will be seen from Figure 3 the inner face of the plate (7) for the cylinder .(1) is concave which will induce the desired flexing of the outer edge of the larger one of the discs (3e) especially since the bolt mountin for the discs (which will now be described) clamps the center area of the discs firmly against the face of the plates.

The bolt mounting preferably includes a head bolt (3k) which passes through co axial openings in the discs (3e), the plate (7 and the outer discs (3g). The outside one of the discs (3g) is made with a short annular sleeve (31) which is made to receive an internally threaded cuff (3m) which in turn receives the threaded end 'of the bolt and bearings against the inner one of the discs (3g) around the bolt opening therein. The spring is coiled around the sleeve (31) with its opposite end bearing against' the wall of the chamber (3i). With construction the cuff (3m) may be relied upon to draw up the bolt (3k) to tightly clamp the discs (3c) against the inner face of the plate and at the same time leave the discs (3g) under the influence of the spring (3i).

One of the salient features of the device resides in an arrangement whereby the air to be stored under pressure is acted upon by the pistons in stages or rather successively; therefore, after'the air has been introduced into the cylinder (l) by the suction stroke of the piston (9) and forced into the chamber (3i) upon a compression stroke of the piston it is introduced to the cylinder (2) through. the by pass pipe (A) which establishes a communication between the chamber (3i) and the distributing channel (2b) in the head This channel like the channel (3) in the head (3a) communicates with the compression chamber of the cylinder (2) through the outer annular row of openings (2C) in the plate (7) for the cylinder (2). The construction of the plate for this cylinder is the same as the plate for the cylinder (l) and the same also applies to the discs (2d) on the inside of the plate, the inner annular row of openings (22), the outer discs (2f) and the spring and its associated parts, such as the sleeve (2h) and the cuff (2i). The springs (2g) and its associated parts in this instance being housed in the outlet chamber which is connected with the storage tank by a pipe line (B). I e

A suitable lubricant may be maintained in the well (5) with a dra-w passage leading from vthe housing. for the drlve y shaft. A level gauge (5b) may be arranged for the well (5)v as shown in Figure (74). Arranged on the top of the crank case is a dome shaped breather casing (4a), the dome (4b) of which having slotted openings (4) which establish a communication from the atmosphere with the crank case (4) through the opening (4d) in the plate (4e). The

rabbetted edge of'the plate (4e) is made to support the breather casing with the same confined thereupon by the central retaining bolt (4f) which is carried by the dome (4b) with its threaded -end received in an opening in the plate as at (4g). An opening (4h) in the dome may serve to provide a filling opening for pouring lubricant into the well (5). A conical screen (4i) confined around the bolt (4f) may serve to exclude foreign matter such as dust.

Outlining the operationof the compressor it should be first taken in consideration that the two pistons are connected as one and reciprocated by means positioned intermediate the same. `When one piston is on a compression stroke the other is on a suction stroke. When the piston (9) is sucking air into its cylinder from the channel (3) the piston (8) is forcing the air from its cylinder into the chamber (21') and through the pipe (B) to the the storage tank. The cooperative relationship of the valves and chambers in the cylinder heads as well as the position of the main intake and discharge enables the air to be acted upon in stages which greatly facilitates the operation of the devices.

I claim:

l. An air compressor, comprising a pair of co-axially arranged cylinders, a pair of rectilinear pistons connected end to end adapted to Work in said cylinders and having a common driving means, said driving means including a shaft having an eccentric head presented transversely to the axis of the pistons, and a rocking yoke pivotally mounted to one of the pistons and connected to the eccentric head whereby the eccentric rotation of the eccentric head may be converted into a reciprocating movement of the pistons, said pivotal mounting for the rockmon driving means, the suction strokeof one piston adapted to admit air into the cylinder therefor, said air adapted to be .transferred by said piston upon its compression stroke to another of said cylinders where it will be acted upon by thepiston therein and transferred to a stored source, said driving means including a shaft having an eccentric head presented transversely to the axis of the pistons, and a rocking yoke pivotally con-4 nected to one of the pistons and connected to the eccentric head whereby the eccentric rotation of the eccentric head may bel con. verted into a reciprocating movement of the pistons, said pivotal mounting for the rocking yoke on one of the pistons comprising a transverse pin confined within the walls. of the piston, and a longitudinal guide rod for the pistons having one end transversely anchored in the end of said pin and with its opposite end received in a guiding opening in the walls. of the compressor crank case.

3. In an air compressor, a pair of cylinders mounted end to end, a piston for each cylinder connected end to end and having a common driving means, a valved port in one cylinder establishing a communication between the atmosphere and the compression chamber of the cylinder whereby air may be introduced into the cylinder upon the suction stroke of the piston thereof, a communication between said cylinder and( the opposite cylinder whereby air may be transferred from the first-named cylinder into the second-namedv cylinder upon the compression stroke of the piston in the rstnamed cylinder, the piston in the secondnamed cylinder adapted to urge the introduction of air into its respective cylinder upon its suction stroke and transfer the same to-a stored source upon its compression stroke, said driving means including a shaft having an eccentric head presented transversely to the axis of the pistons, and a rockl ing yoke pivotally mounted to one of the pistons and connected to the eccentric head whereby the eccentric rotation ofthe eccentric head may be converted into a reciprocating movement of the pistons, said pivotal mounting for the rocking yoke on one of the pistons comprising `a transverse pin confined within the walls of the piston, and a longitudinal guide rod for the pistons having one end transversely anchored in the end of said pin and with its opposite end received in a guiding opening in the walls of the compressor crank case.

4. In an air compressor, a -pair of opposed cylinders mounted end to end, a pair of rectilinear pistons adapted to work in said cylinders, said pistons being connected together and having a common driving means, `a valved .intake port establishing a. communicationr between the atmosphere and the compression chamber of one of the 'cylinders whereby air may be introduced into the cylinder by the suction stroke of the piston therein, a distributing chamber associated with said cylinder, a valved port establishing a communication between the compression chamber thereof and said distrib-l uting chamber whereby air may transferred from saidv compression chamber into said distributin chamber upon a compression stroke o the piston, a connection between said distributing chamber and said opposite cylinder for transferring the air from said distributing chamber tosaid opposite cylinder, a piston in said opposite cylinder adapted to urge the introduction of air through said connection and into the compression chamber of the cylinder upon its suction stroke, said cylinder having a connection with a source of stored air wherebythe air thus introduced into the compression chamber may be transferred to said source of stored air upon the compres- Nsion stroke of the piston, said driving means including a shaft having an eccentric head presented transversely to the axis of 'the pistons, anda rocking yoke pivotally mounted to one of the pistons and connected `to the eccentric head ywhereby the eccentric rotation of the eccentric head may be con-v verted into a reciprocating movement of the pistons, said pivotal mounting for the rocking yoke on one of the pistons comprising a transverse pin confined within lthe walls of thev piston, and a longitudinal guide rod for the pistons having one' end transversely anchored in the end of said pin and with its opposite end received in a guiding opening in the walls of the compressor crank DEXTER C. BAKER. 

